Abstract
Non-alcoholic fatty liver disease (NAFLD) has emerged as the most common cause of chronic liver disease worldwide, with a rising prevalence in India due to increasing rates of obesity, diabetes, and sedentary lifestyles. This article reviews the pathophysiology, risk factors, diagnostic approach, and current treatment strategies for NAFLD, with a focus on the Indian context. Early detection and lifestyle interventions are key to managing this silent but potentially progressive disease.

Introduction

Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of liver conditions ranging from simple steatosis to non-alcoholic steatohepatitis (NASH), which can progress to fibrosis, cirrhosis, and hepatocellular carcinoma (Younossi et al., 2018). In India, lifestyle transitions and urbanization have led to a sharp increase in NAFLD prevalence, now estimated at 25–32% in the general population (Duseja & Chalasani, 2014). Despite its rising burden, NAFLD remains underdiagnosed and undertreated.

Pathophysiology

NAFLD is primarily driven by insulin resistance and metabolic dysfunction. Excess caloric intake and reduced physical activity promote fat accumulation in hepatocytes. This triggers oxidative stress, inflammation, and in some cases, hepatocyte injury and fibrosis (Rinella, 2015). NAFLD is considered the hepatic manifestation of metabolic syndrome and is often associated with obesity, type 2 diabetes mellitus (T2DM), dyslipidemia, and hypertension.

Risk Factors

The major risk factors for NAFLD in the Indian population include:

• Obesity and central adiposity, particularly in urban populations
  
  

• Type 2 diabetes mellitus
  
  

• Dyslipidemia
  
  

• Sedentary lifestyle and poor dietary habits
  
  

• Genetic predisposition – e.g., PNPLA3 gene polymorphism
  
  

Studies suggest that even individuals with normal BMI (termed "lean NAFLD") are at risk due to high visceral fat and insulin resistance (Das et al., 2010).

Diagnosis

NAFLD is typically suspected in asymptomatic patients with elevated liver enzymes or incidental imaging findings. Key diagnostic tools include:

• Ultrasonography – first-line due to its accessibility
  
  

• Liver function tests – may show mildly elevated ALT/AST
  
  

• FibroScan (elastography) – to assess fibrosis non-invasively
  
  

• Liver biopsy – gold standard for diagnosing NASH and staging fibrosis
  
  

Non-invasive scoring systems like the NAFLD Fibrosis Score (NFS) or FIB-4 index can help stratify fibrosis risk (Angulo et al., 2007).

Management

Currently, no pharmacological therapy is approved specifically for NAFLD. Management focuses on lifestyle modifications:

• Weight loss (≥7–10%) is the most effective intervention
  
  

• Dietary changes – reduced saturated fats, refined carbs; Mediterranean diet is preferred
  
  

• Regular physical activity – at least 150 minutes of moderate-intensity exercise per week
  
  

In select cases, medications such as pioglitazone or vitamin E may be considered in non-diabetic patients with biopsy-proven NASH (Chalasani et al., 2018).

Conclusion

NAFLD is a growing public health challenge in India, driven by rising rates of metabolic syndrome and sedentary behavior. Primary care physicians and medical students must be aware of this condition’s significance, as early intervention can prevent long-term liver damage. Community awareness, dietary reform, and preventive screening programs are essential for tackling the NAFLD epidemic in India.

References

Angulo, P., Hui, J. M., Marchesini, G., Bugianesi, E., George, J., Farrell, G. C., ... & Day, C. P. (2007). The NAFLD fibrosis score: A noninvasive system that identifies liver fibrosis in patients with NAFLD. Hepatology, 45(4), 846–854. https://doi.org/10.1002/hep.21496

Chalasani, N., Younossi, Z., Lavine, J. E., Charlton, M., Cusi, K., Rinella, M., ... & Sanyal, A. J. (2018). The diagnosis and management of nonalcoholic fatty liver disease: Practice guidance from the American Association for the Study of Liver Diseases. Hepatology, 67(1), 328–357. https://doi.org/10.1002/hep.29367

Das, K., Das, K., Mukherjee, P. S., Ghosh, A., Ghosh, S., Mridha, A. R., ... & Dhali, G. K. (2010). Nonobese population in a developing country has a high prevalence of nonalcoholic fatty liver and significant liver disease. Hepatology, 51(5), 1593–1602. https://doi.org/10.1002/hep.23567

Duseja, A., & Chalasani, N. (2014). Epidemiology and risk factors of nonalcoholic fatty liver disease (NAFLD) in Asian populations. Hepatology International, 7(4), 755–770. https://doi.org/10.1007/s12072-013-9480-3

Rinella, M. E. (2015). Nonalcoholic fatty liver disease: A systematic review. JAMA, 313(22), 2263–2273. https://doi.org/10.1001/jama.2015.5370

Younossi, Z. M., Koenig, A. B., Abdelatif, D., Fazel, Y., Henry, L., & Wymer, M. (2016). Global epidemiology of nonalcoholic fatty liver disease—Meta‐analytic assessment of prevalence, incidence, and outcomes. Hepatology, 64(1), 73–84. https://doi.org/10.1002/hep.28431